During the production of cured refractory material (e.g., bricks, tiles, ceramics and the like which will hereinafter be collectively referred to as "ware"), kiln cars are continually recycled from the exit of the tunnel kiln (after the cured ware has been off-loaded) to a marshalling track (where uncured ware is placed upon the kiln car in preparation for its entry into the tunnel kiln). It is therefore oftentimes necessary for transfer cars to be employed at entrances/exits of tunnel kilns in order to direct kiln cars between the marshalling tracks and the exit/entrance of the tunnel kiln.
Sometimes, the marshaling tracks are a part of a preheater or cooling tunnel which is disposed adjacent to the tunnel kiln--that is, the marshalling tracks are completely enclosed by a housing making them, in essence, an integral part of the tunnel kiln. The kiln cars loaded with ware may therefore be transferred to/from the tunnel kiln within the enclosed marshalling tracks so that the ware is preheated or cooled to the desired extent. This known practice of transferring kiln cars along marshalling tracks in a closed housing, however, is disadvantageous since the entire kiln car is subjected to elevated temperatures which may be damaging to the kiln car's undercarriage.
A kiln car transfer system is also known (Swindell-Dressler Tunnel Kiln in use with Globe Brick, Ohio, USA) which includes an insulated housing adapted to accommodate a kiln car. The housing itself is capable of being moved along tracks in the longitudinal direction of the tunnel kiln. However, one significant disadvantage of this prior system is that the kiln car mechanisms which transfer the kiln car to/from the tracks in the housing may be elevated to extreme temperatures by virtue of heat radiating from the cured ware unless the kiln car transfer is accomplished within a minimal time frame.
What has been needed in this art, therefore, is a transfer apparatus onto which kiln cars may be advanced so as to accommodate upstream tunnel kiln processing, while at the same time, protect the transfer mechanisms from excessive heat radiating from the ware loaded on the kiln car. It would also be highly desirable if the radiated heat from the ware was minimized so as to, in turn, minimize any adverse effect which may result from the ware being cooled to an undesirable extent. It is towards satisfying such needs that the present invention is directed.
According to the present invention, an especially adapted kiln car transfer apparatus is provided which includes a transfer carriage for supporting at least one kiln car. The transfer carriage itself is supported upon transverse tracks so as to be capable of movements between adjacent ends of a pair of tunnel kilns.
A generally inverted U-shaped housing is carried by the transfer carriage and defines an interior space sized and configured to accept a kiln car. Important to the present invention is the disposition of a movable wall structure within the housing's interior space. The wall structure may thus move reciprocally between the opposing open ends of the housing in response to the continual advancement/discharge of the kiln car onto/from the transfer carriage, and hence, into/from the interior space defined by means of the housing. In such a manner, the movable wall minimizes heat build-up within the transfer apparatus, since only a minimal region of the transfer apparatus is potentially exposed directly to heat radiating from the ware at any give time during the transfer operation--i.e., due to the moveable wall effectively blocking the radiated heat. Heat build-up is further minimized by transverse seal structures associated with the movable wall which provide a transverse thermal seal between the movable wall and the kiln car. Hence, this transverse seal structure effectively thermally isolates the undercarriage of the kiln car and the transfer carriage from the heated ware borne by the kiln car.
The housing itself may be mounted for movements towards and away from the tunnel kiln with which it is aligned. This capability of the present invention allows the housing to, in essence, be an integral extension of the tunnel kiln (so as to minimize, if not eliminate, thermal "shock" on the ware and/or to substantially maintain the internal environment of the tunnel kiln) when the kiln cars are transferred onto/from the transfer carriage. Moveable mounting of the housing also facilitates its separation from the tunnel kiln when the kiln car is to be transferred to another tunnel kiln via the transfer carriage.
These, and other aspects and advantages of the present invention will become more apparent after careful consideration is given to the detailed description of the preferred exemplary embodiments thereof which follows.